Multiple density separator

ABSTRACT

The specification discloses a multiple density separator comprising an outer cylinder, a spaced inner cylinder located within the outer cylinder forming a material separating chamber therebetween, and an inlet formed in one end of the separating chamber for allowing the flow of material from the inlet toward the other end of the separating chamber. A discharge cylinder is located within the inner cylinder and a truncated cone is connected between the inner cylinder and the discharge cylinder. A plurality of lower bypass passages are formed through the inner cylinder to allow the lower density materials within the separating chamber to flow inward into the discharge cylinder by way of a bypass chamber. Extending inward from the inner cylinder are a plurality of upper flow turners for allowing the low density materials in the separating chamber downstream from the bypass passages to flow inward without re-mixing to a main flow chamber which is in communication with the discharge chamber. Formed in the separating chamber at the top end of the separator are a plurality of annular passages having discharge conduits for separating and discharging the higher density materials from the separating chamber. Coupled to the ends of the discharge conudits are nozzles which discharge the materials in a circular path in a direction opposite the direction of rotation of the separator. Also provided in the separator next to the wall of the outer cylinder is a screen which is vibrated to convey the material up the separating chamber and to enhance settling of the materials. Also provided is a filter located next to the inner wall of the inner cylinder to filter the materials flowing inward through the bypass passages.

United States Patent n 1 Underwood l l MULTIPLE DENSITY SEPARATOR [76] Inventor: Gene E. Underwood, PO. Box 1759,

Casper, Wyo. 8260l [22] Filed: Dec. 14, 1973 [21] Appl. No: 424,773

[52] US. Cl. 233/2; 233/3; 233/l5; 233/22: 233/23 R; 233/46 [51] Int. CL... 8048 5/06; 804B 7/18; B04B 11/06 [58] Field of Search l. 233/] R, 2 3, l6. 17,

233/18, 2l, 22, 27. 28. 46, 47 R, 19 R, 23 R [56] References Cited UNITED STATES PATENTS 1.257.235 2/l9l8 Howell 4. 233/28 2,084,487 6/l937 Haraldson.. 233/27 X 2.594.445 4/[952 Keith 233/2 3,443.748 5/l969 Hooper t t l 233/28 3,5 l) 2(ll 7/1970 Eiscl ct al. 233/46 X Primary Exumim'r(]eorge H. Krizmanich [57] ABSTRACT The specification discloses a multiple density separator comprising an outer cylinder, a spaced inner cylinder located within the outer cylinder forming a mate' rial separating chamber therebetween, and an inlet formed in one end of the separating chamber for allowing the flow of material from the inlet toward the avg:

other end of the separating chamber. A discharge cylincler is located within the inner cylinder and a truncated cone is connected between the inner cylinder and the discharge cylinder. A plurality of lower bypass passages are formed through the inner cylinder to allow the lower density materials within the separating chamber to flow inward into the discharge cylinder by way of a bypass chamber. Extending inward from the inner cylinder are a plurality of upper flow turners for allowing the low density materials in the separating chamber downstream from the bypass passages to flow inward without re-mixing to a main flow chamber which is in communication with the discharge chamber.

Formed in the separating chamber at the top end of the separator are a plurality of annular passages having discharge conduits for separating and discharging the higher density materials from the separating chamber. Coupled to the ends of the discharge conudits are nozzles which discharge the materials in a circular path in a direction opposite the direction of rotation of the separator. Also provided in the separator next to the wall of the outer cylinder is a screen which is vibrated to convey the material up the separating chamber and to enhance settling of the materials. Also provided is a filter located next to the inner wall of the inner cylinder to filter the materials flowing inward through the bypass passages.

16 Claims, 22 Drawing Figures SHEET 1 BF 7 PATENTED 9'97?) 3.904.109

SliZET 3 BF 7 PATEN TED 35F 975 swan u o 7 PATENIEUSEP 9am 3,904,109

saw 5 BF 7 223A 224A 222A 22/A 224 224A 225A 222A MULTIPLE DENSITY SEPARATOR BACKGROUND OF THE INVENTION This invention relates to a centrifugal and vibratory screen separator and more particularly to a separator useful in separating the components of drilling fluids to recover materials used therein.

In the oil field industry, cyclone separators are used to process the drilling fluid or mud to eliminate undesirable solids such as sands, silt, etc. Separators of this type operate by injecting the material to be separated at a high velocity against a stationary cylinder and cone. Such separators have disadvantages in that they require a large amount of power for operation and moreover do not adequately separate the small particles and will not recover materials such as barite and bentonite.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a multiple density separator which is efficient, and avoids the disadvantages of the known separators used for example. in the oil industry.

In one aspect, the present separator comprises structure forming an outer chamber, structure forming an inner chamber located within the outer chamber and means for rotating the chambers. The outside wall surface of the inner chamber is spaced from the inside wall surface of the outer chamber forming a material separating chamber therebetween. An inlet is formed in one end of the separating chamber at one end of the separator for allowing the flow of material from the inlet toward the other end of the separating chamber while the chambers are rotating. Inward flow means is provided for flowing the material next to the outside wall of the inner chamber inward and which is discharged out of the separator by discharge means. In addition, there is provided separate flow means for flowing the material next to the inside wall of the outer chamber out of the separating chamber.

In one aspect, a plurality of axially spaced passages extend through the wall of the inner chamber to allow the fluid next to the outside wall of the inner chamber to flow inward. In a further aspect, there is provided a discharge chamber located in the inner chamber and having one end located near said first end of said separator and a discharge end extending through the other end of the separator. Wall means are located between the inner chamber and the discharge chamber for providing at least two different flow paths extending from the axially spaced passageways toward the first end of the separator. A first of the two different flow paths extends from a group of upstream passages formed through the wall of the inner chamber while a second of the two different flow paths extends from a group of downstream passages formed through the wall of the inner chamber. First inner passages are formed in the discharge chamber at said one end in communication with the first of said two different flow paths. In addition, second inner passages are formed in the discharge chamber at said one end in communication with the second of said two different flow paths. Means is provided for adjusting the size of the first and second inner passages to selectively vary the flow rate of the materials flowing through the two different flow paths.

In another aspect, there is provided flow tumers for positioning the material flowing through the passages at different radial positions dependent upon the density of the material. The flow turners comprise conduits extending radially inward and axially spaced from each otherv The downstream conduits have lengths less than the upstream conduits.

In the embodiment disclosed, the outer and inner chambers comprise cylindrical chambers defining the separating chamber as an annular chamber located between the outside wall surface of the inner chamber and the inside wall surface of the outer chamber. The separate flow means is located downstream of the axial passages and comprises a plurality of annular passages rotatable with the inner and outer cylindrical chambers and which have openings in communication with the annular chamber at different radial positions. Flow conduit means extend from the annular passages out of the rotatable cylinders. The flow conduit means associated with each annular passage have inlet means for allowing the flow of material from the annular passages through the flow conduit means. The inlet means are adjustable in size for adjusting the flow rate of material flowing from the annular passages through the flow conduit means.

The flow conduit means associated with each annular passage has discharge nozzle means located at different radial positions outside of the outer cylindrical chamber to discharge the flow from each annular passage at a different radial position. Means is provided for separately receiving the material discharged from each annular passage by way of its associated flow conduit means and nozzle means.

The nozzle means extend generally tangent to the circles formed upon rotation and in directions opposite the direction of rotation.

In a further aspect, there is provided a vibratory means located in said separating chamber and means for vibrating the vibratory means while the chambers are rotating. In addition, there is provided filter means located next to the inside wall of the inner chamber and in the flow path of materials flowing through said upstream passages.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 schematically illustrates a cross section of the separator of the present invention;

FIG. 2 is en enlarged cross sectional view of the lower end of the separator of FIG. 1;

FIG. 3 is an enlarged cross sectional view of the top end of the separator of FIG. 1 as seen when taken through the lines lII-lll of FIG. 14;

FIG. 4 is a perspective view of the inlet through which fluid is injected into the separator;

FIG. 5 is an enlarged view ofa portion of the exterior of the inner cylinder of FIG. 1 showing a set of bypass passages for bypass flow;

FIG. 6 is a perspective view of a portion of the top of the separator looking downward at an angle from a level defined by line 6-6 of FIG. 1;

FIG. 7 is a perspective view ofa value control mechanism;

FIGv 8 is an exploded view of the collar and trunnion of the control mechanism of FIG. 7;

FIG. 9 is a perspective view of annular discharge chambers for receiving the heaview density materials;

FIG. 10 is an enlarged cross sectional view of one of the heaview density material discharge conduits of FIG.

FIG. 11 is an enlarged cross sectional view of one of the actuator blocks of FIG. 3;

FIG. 12 is a cross sectional view of FIG. 11 taken through the lines 12-12 thereof;

FIG. 13 is a perspective view of the top portion of the se arator of FIG. 3 looking upward at an angle showing one of the actuator blocks and sleeves for holding the discharge conduits;

FIG. 14 is a view similar to that of FIG. 13 illustrating the nozzles of the heavier density material discharge conduits;

FIG. 15 is an enlarged cross sectional view of one of the nozzles of FIG. 14;

FIG. 16 is an end view of the nozzles of FIG. 15 taken along the lines 16-16 thereof;

FIG. 17 is an enlarged cross sectional view of the top portion of the separator of FIG. 3 looking downward and illustrating an actuator block and radial control rods for vibrating a vibratory screen;

FIG. 18 is an enlarged cross sectional side view of the top portion of the separator of FIG. 3 illustrating a connecting rod connected to a radial control rod for vibrating the vibratory screen;

FIG. 19 is a cross sectional view of FIG. 17 taken along the lines l919 thereof but with a portion of the structure removed;

FIG. 20 is a cross sectional view of FIG. 17 taken along the lines of 20-20thereof;

FIG. 2] is an enlarged cross sectional view illustrating the vibratory screen connected to a connecting rod and 'the lower end of the vibratory screen; and

FIG. 22 illustrates a hydraulic system for vibrating tube 249 and hence the vibratory screen.

Referring now to FIGS. 1-6, the multiple density separator is identified by reference numeral 21, and is supported for rotation about a vertical axis while material to be separated is injected into the separator at its lower end 21A and separated material is discharged from the separator from its upper end 2lB. In the following description, the separator will be described as employed for separating drilling fluids, in which case the materials to be separated are gases, liquids, and solids. It could be used however, to separate other types of fluids or materials. The separator comprises an outer cylinder 23, an inner cylinder 25, an inner discharge cylinder 27, and a truncated cone 29, all of which are connected together and hence rotate together. The outer cylinder 23 has a bottom end 31 and top end 33 connected thereto which in turn are connected to a lower tubular shaft 35 and an upper tubular shaft 37 respectively. Shaft 35 is supported for rotation by bearings 43 connected to stationary support member 47 while shaft 37 is supported for rotation by bearings 49 connected to stationary support member 51. Thrust bearing 52, supported by support tube 52A connected to support beam 52B, prevents axial movement of the rotating assembly. Although not shown. stationary support members 47 and 51 and 52B are connected together. Connected to shaft 35 is a sprocket means 53 which is driven by a chain 55, a sprocket drive 57, and a motor 59 for rotating shaft 35 and hence the separator 21. A stationary support illustrated at 59A, is provided for supporting the motor 59.

Extending through tubular shaft 35 is an intake or inlet 61 into which fluid or material to be separated is injected. In the inlet 61, the fluid or material flows through a two-bladed impeller 61a and by way of a chamber C to an annular chamber D formed between cylinders 23 and 25. The impeller 61a rotates with the shaft 35 as the separator is rotated. As illustrated in FIG. 4, chamber C includes a plurality of spaced vanes 62 employed for support purposes and for evenly distrubuting the flow from inlet 61 into chamber D. The vanes are connected between the bottom end 31 and member 63, the latter of which forms the bottom end of cylinder 25. In annular chamber D, the materials flow upward and are separated due to the centrifugal force imparted as the separator is rotated whereby the higher density materials are forced next to the inner surface of outer cylinder 23 while the lower density materials are displaced to the outer surface of inner cylinder 25.

From annular chamber D, the lower density materials next to the outer surface of cylinder 25 flow inward into a bypass chamber or flow path H and into a main flow chamber or flow path 8. The truncated cone 29 separates chambers H and S. Flow into bypass chamber H is by way ofa plurality of axially spaced sets of apertures G1-G6 while flow into the main flow chamber S is by way of radially inward extending conduits 71-79 downstream of apertures Gl-G6. In FIG. 6, radial conduits 71 are not illustrated. As the separator is spun, the material or fluid in chambers H and 8 flow downward and then into a central discharge chamber U formed within the discharge cylinder 27. Flow into discharge chamber U is by way of passages formed in the lower end of the discharge cylinder 27. Due to the effect of centrifuging and due to the arrangement for flowing fluid ormaterial into chamber U, the lower density fluid or material will be located and will flow upward centrally around the axis of cylinder 27 while the higher density fluid or material will be located and will flow upward at positions radially outward from the axis. Two discharge ports are provided for discharging the fluid or material from chamber U as materials of two different densities. Thelow density materials designated as density 1, flow outward by way of a conduit 81, connected for rotation to shaft 37 and then through stationary conduit 83 and a stationary port 85 connected thereto. The higher density materials designated as density II, flow upward through the annular space formed between conduit 81 and shaft 37, along flow paths illustrated by arrows 86 (see FIG. 3), and then outward through a stationary discharge port 87 by way of openings 89 formed through an upper extension of shaft 37.

Upstream of conduits 71-79, the higher density materials, in annular chamber D, flow into radially spaced annular passages 91-94 for separation according to their densities. These densities, from lower to higher, may be defined as densities III-N. From these annular passages, the separated materials are discharged out of the separator through discharge conduits 101-104, the materials of lower density III being discharged through the radially longer conduits 101, while the materials of higher densities lV-N being discharged through the conduits 102-104 respectively of progressively shorter radial length.

In FIG. I, apertures GI-G6 are illustrated as conduits projecting inward a small distance from cylinder 25 for clarity of illustration, although in practice they are apertures or openings extending through the cylinder 25 and do not extend inward. As shown in FIG. 5, each set of axially spaced apertures Gl-G6 comprises three rows of apertures formed around the circumference of inner cylinder 25. In FIGv 5. the axis of cylinder 25 is along lines A-A. The purpose of apertures (ll-G6 and the bypass chamber H are to rcmove the lower density fluid or material from the annular charnber D as soon as it is separated in order to provide more time to Separate or centrifuge the unclarificd or unscparated material in the annular chamber D thereby obtaining enhanced separation for the balance of the ma terial in the chamber D. The balance of the lower density material which do not flow into bypass chamber H, flow into main flow chamber S by way of the conduits 7179, as indicated above. As illustrated in FIGS. 1, 3, and 6, the conduits 7l77 extend radially inward of the cylinder 25 with the conduits 71 having the longest length and the conduits 7l77 downstream decreasing in lengthv Conduits 78 and 79 are apertures formed through cylinder 25 and hence have a length equal to the thickness of the wall of cylinder 25. With this arrangement. material of the lowest densities downstream of passages (31-06 will flow through longer conduits 71 and will be placed next to discharge cylinder 27 within chamber S. The next higher density materials will flow through conduits 72 and the materials of increasingly higher densities next to the outer surface of cylinder 25 will flow into chamber S through conduits 73-79 respectively Thus the conduits 7179 are in effect flow turners which allow the balance of the lower density materials in annular chamber D downstream of openings G1G6 to flow into the main stream flow chamber S without re-mixing. Since the conduits 7l79 extend inward to different radial position, the material thus will flow into chamber S in a laminated manner whereby the lighter density materials will be located next to the discharge cylinder 27 while in the progressively higher density materials will be located radially outward. Conduits 7l79 have a large flow area to obtain a low flow velocity radially inward which prevents higher density particles of small size from being discharged through density I and density 11 discharge ports.

Also extending radially outward from cylinder 25 and into annular chamber D, at a level below the conduits 71, are a plurality of conduits 111 located around the circumference of cylinder 25. These conduits 111 provide flow paths from chamber S to chamber D and their purpose is to reintroduce into chamber D any coelesing or grouping of materials which occur in chamber S. Such materials will separate next to the cone 29 and flow in a counter-flow direction in chamber S upward and back out into annular chamber D away from the outside surface of cylinder 25 whereby they may be properly separated by annular passages 9194.

Referring now to FIG. 2, there will be described in detail the passages formed at the lower end of the discharge cylinder 27 and a selector valve mechanism for adjusting the flow rate of the materials flowing inward by way of chambers H and Sv Extending outward from the discharge cylinder 27 are a plurality of radial conduits 113 which extend through the cone 29 and into the chamber H near the wall of inner cylinder 25. These conduits are provided to allow the higher density materials in chamber H next to the wall 25 to flow into the discharge chamber U to a radial position near its cylindrical wall 27. The lower density materials in by pass chamber H flow back behind the cone 29 and into the discharge cylinder 27 by way of an opening 115 formed through axial conduit 117 extending from plate 119 connected to cone 29. From opening 115, the materials tlow through ports 12] formed through cylindri cal member 123, which is connected to axially adjustable control rod 125 which extends upward through the other end of the separator. Cylinder 123 is slidable around conduit 117 and may be adjusted by rod 125 to different axial positions to adjust the flow through ports 121.

Also extending from the cylinder 27 are a plurality of outward extending radial conduits 131 which extend into the chamber S away from the wall of the discharge cylinder 27. These conduits are provided for allowing the higher density materials in chamber S to flow into the discharge chamber U next to the wall 27. Extending from cylinder 27 into the discharge chamber U below conduits 131 and 113 are a plurality of radial conduits 141, 143, and 145 which have decreasing radial lengths respectively. Thus in chamber S. downstream of conduits 131, the lowest density materials next to the wall of cylinder 27 will flow radially inward to a position near the axis of the discharge chamber u. in chamber S, downstream of conduits 141, materials next to the wall of cylinder 27 and of increasing higher densities will flow through conduits 143 and 145 respectively. The balance of the materials in chamber S and next to the wall of cone 29 will flow behind the end of cylinder 27 and into chamber U through annular flow path 147. Thus conduits or passages 131, 141, 143, 145 and 147 form flow turners which introduce the materials from chamber S. without re-mixing, into the discharge chamber U, at radial positions according to their densities. Similarly, conduits 113 and axial flow path introduce the materials from bypass chamber H, without remixing, into the discharge chamber U at radial positions according to their densities.

Also connected to the control rod for axial movement therewith is a cylinder 151. Cylinder 151 is connected to rod 125 by way of radial spokes not shown. Cylinders 123 and 151 comprise a selector valve mechanism which may be moved axially to different positions, by axial movement of rod 125, to adjust or vary the flow rate of material from chambers S and H into the discharge cylinder 27. For example, if it is desired to completely cut off flow through bypass chamber H, then the control rod 125 will be moved a full distance downward until the shoulder 123A of cylinder 123 abuts against the end 117A of conduit 117. In this position, the openings 12] will be completely closed by the conduit 117 while the walls of the cylinder 151 will completely close the passageways formed through conduits 113. It may be desirable in one example to completely cut off flow through bypass chamber H in the event that the material injected through inlet 61 includes relatively large but low density particles which could not flow through openings 01-66 and hence would otherwise plug up these openings if the bypass chamber H were open.

There may be other instances when maximum bypass flow is desired, at which time the control rod 125 will be located at the maximum upper position as shown in FIGv 2. In this position, conduits 113 and openings 121 will be fully openv Conduits 131 also will be completely closed by cylinder 151, however material will still flow into the discharge chamber 27 from the main flow chamber S by way of conduits 141, 143, 145, and annular passage 147.

The control rod 125 can be adjusted to any position between its maximum upper and lower positions to vary the amount of flow through conduits 131, 113, and openings 121. In normal operations, the control rod 125 may be located at a mid-position to locate the cylinder 151 about midway between conduits 131 and 113 whereby conduits 131 and 113 will be open about half-way. At this mid-position, the upper openings 12] in cylinder 123 will be open while the lower openings 121 will be closed. Thus at the mid-position of the control rod 125, the material which flows through conduits 131 and 113 and through openings 121 will be about 50% of maximum.

Referring to FIGS. 1-3, it can be seen that the control rod 125 extends upwardly through the discharge chamber U, through the tubular shaft 37, through the tubular support 52a and through the support beam 528 and is connected to a trunnion and collar assembly which in turn is connected to a linkage mechansim employed for adjusting the control rod 125 and hence the selector valve mechanism to a desired axial position.

Referring to FIGS. 7 and 8, a suitable trunnion and collar assembly and linkage mechanism will be described although the arrangement shown in FIG. 7 is illustrated as being coupled to one of the tubes 245 surrounding the rod 125 for controlling flow to the discharge conduits 103. In FIG. 8, the trunnion is illustrated at 401 and comprises a cylindrical member 402 which has an open top end and a bottom 403 with an aperture 404 formed therethrough for receiving the tube 245. Located within the trunnion is an annular thrust bearing member 405, a collar 407 and an annular thrust bearing 409. The collar is fixedly attached to the tube 245 by way of set screws 411 which are threaded into the collar and into apertures 245A formed in the tube 245. The trunnion is held in place around the collar by an annular washer 413 which is threaded into the top of the cylinder 402 with the thrust bearings 405 and 409 located on opposite sides of the collar 407. With this arrangement, the collar 407 rotates with the tube 245 within the trunnion 401 which remains stationary and may be employed to impart axial adjustment to the tube 245 by moving the trunnion 401 up or down by way of extending pivot members 402A which fit into slots 415 of a fork 417. The

fork 417 is connected to a linkage 419 by way ofa shaft 421 splined into the fork 417 and into the linkage 419 whereby the fork 417 and the linkage 419 are fixedly secured to each other. The shaft 421 is pivotally supported by means not shown whereby movement of the end 419a of the linkage 419 in the directions of the ar rows 423 or 425 will cause the fork 417 to move the trunnion and hence the tube 245 up or down. The linkage end 4191: may be moved up or down by a push rod 427 having its top end pivotally connected to the linkage by way of pivot member illustrated at 429. Rod 427 may be moved vertically up or down by a rotatable wheel 431 threaded to the lower end 427a of the push rod 427 and located between two arms 433 and 434 of a support member 435 which is fixed in place to struc ture not shown.

For use for adjusting the vertical position of rod 125, a trunnion and collar assembly and linkage assembly similar to that shown in FIGS. 7 and 8 will be employed with the collar and trunnion coupled to the top end of control rod 125.

Referring again to FIG. 3, upon flow of the materials upward through discharge cylinder 27. the higher density materials will flow next to the wall of cylinder 27 and through the annulus formed between shaft 37 and conduit 81. From the annulus, the material will flow through slots or openings 89 to stationary discharge port 87, which in the embodiment of FIG. 3 preferably is an Archimedes spiral. From port 87, the materials may be discharged into a storage tank, or they may be remixed with other desirable drilling fluid components in the event the system is used for separating contaiminated drilling fluids in which event the material discharged from port 87 will be water or oil. The lower density materials will flow upward tlirough rotating conduit 81 into stationary conduit 83 and then through stationary port 85. In the event the system is used for separating contaminated drilling fluids, the material discharged through port 85 will be a gas which will be disposed of.

Referring to FIG. 3, there will be described the annular passageways 9194 for separating the higher density materials in the annular chamber D and for discharging these materials out of the separator. These annular passageways are formed by the top portion of cylinder 23 and by four annular cylinders 201-204 connected to the top end 33 of the outer cylinder 23 and which have flared lower ends 21 1-214, which flare outward to different radial positions within the annular passage D. With this arrangement, the materials within annular chamber D downstream of conduits 7l79 will flow into a given annular passage depending upon the density of the material and hence its radial position within the annular chamber D. For example, the lower density materials in chamber D which do not flow into the chamber S will flow into annular passage 91, while the next higher density materials will flow into annular passage 92. Each annular passage 91-94 has four radial conduits associated therewith for discharging the material from the annular passages into separate annular chambers surrounding the separator. For example, four radial conduits 101 are associated with annular passage 91 although only one is shown in FIG. 3. (See also FIG. 1.) Similarly four radial conduits 103 are associated with annular passage 93 although only one is shown in FIG. 3. These conduits rotate as the separator and have nozzles at their ends to discharge the material from the annular passages into stationary annular chambers 221-224 as the separator rotates or is spun. Chambers 22I224 are supported in the positions illustrated in FIG. 3 by means not shown. As seen in FIG. 9, three discharge conduits are connected to each annular chamber 221-224 for collecting the separated materials in the annular chambers 221224. These discharge t nduits are identified at 221A, 222A, 223A, and 224A. In the event the separator is employed to separate contaminated drilling fluids, chambers 221224 for example may contain barite, sand and silt, bentonite, and water respectively for a given drilling fluid. The barite, bentonite and water then may be recombined with the water or oil from discharge port 87 and ap plied back to the mud pump for recirculation.

Referring also to FIG. 10, the discharge conduit 103 will be described in detail. As shown, it extends through a surrounding sleeve 231 which has openings 233 formed therethrough at the radius of the annular passage 93. Sleeve 231 can be rotated with respect to con duit 103. Conduit 103 is stationary with respect to cylinder 23. Also formed through conduit 103 are o enings 235 at the radius of the annular passage 93. The sleeve 231 is adapted to be rotated about the conduit 103 to align or misalign the openings 233 and 235 to thereby adjust the flow rate of the materials flowing from the annular passage 93 into the conduit 103. The adjusting means comprises a rod 241 connected to the inward end of the sleeve 231 and which is coupled to an actuator block 243 (see FIG. 3) which in turn is connected to the tubular thrust member 245. Tubular member 245 telescopes around two inner tubular members 247 and 249 surrounding the control rod 125 and also within two outer tubular members 251 and 253. The top end of tubular member 245 has coupled thereto a collar and trunnion assembly 410 and a linkage assembly as described above for adjusting the tubular member 245 to different axial positions. In FIG. 3, the linkage assembly is not illustrated although a linkage assembly 419 and 427 is illustrated as coupled to a trunnion and collar 285 for adjusting tube 253. As the tube 245 is moved to different axial positions, it moves the actuator block 243 and causes the rod 241 to rotate in its housing sleeve 257. As rod 241 rotates, it rotates the sleeve 231 about conduit 103 thereby varying the size of the passageways through openings 235, 233.

Referring to FIGS. 11l3, the actuator block 243 has four radial rods 24] which are splined to torque arms 261. Torque arms 26] are movably coupled to the actuator block 243 by way of bolts 263 which loosely extend through slots 261A formed in the arm 261. Axial movement of the actuator block 243 by axial movement of its tube 245 will cause the bolts 263 to rotate the torque arms 261 in a manner to pivot the torque arms 261 about the axis of rods 24]. Since the torque arms 261 are splined to rods 241, the rods 241 will ro tate thereby rotating the sleeves 231. Thus as the actuator block 243 is moved up or down to different positions, all of the rods 24] and hence all of the sleeves 231 will be rotated to align or misalign the openings 233 of sleeves 231 with respect to openings 235 of con duits 103 to vary the size of the passageways from the annular passage 93 into the conduit 103.

Each of the other radial conduits 101, 102, and 104 associated with each of the other annular passages 91, 92, and 94 have an actuator block also controlled by a thrust tube for adjusting the size of the passageways from the annular passages into the radial conduits. For example, as illustrated in FIG. 3, actuator block 271 is coupled to tube 253 for adjusting the size of the passageways from annular passage 91 into conduit 101. Actuator blocks 272 and 274 are coupled to tubes 251 and 247 respectively and are employed for adjusting the size of the passageways from annular passages 92 and 94 into conduits 102 and 104 respectively. The top ends of tubes 247, 251, and 253 are connected to trun nions and collars 281, 283, and 285 respectively for adjusting the tubes 247, 251, and 253 to different axial positions. Thus each of the tubes 253, 251, 245, and 247 may be telescoped or moved independent of each other to various axial positions to adjust the size of the passageways from the annular passages 91-94 into the radial conduits 101104. This is desirable in order to equalize the discharge rate through conduits 101 104 with the rate at which the various materials are entering inlet 61. A linkage assembly as described above is coupled to each of the trunnions and collars 285, 283, 401, and 281 for adjusting the axial positions of the tubes 253, 251, 245, and 247 and hence the desired size of the passageways between annular passages 91-94 and conduits 101104 respectively.

Referring now to FIGS. 14-16, there will be described the nozzles coupled to each of the discharge conduits 101104. Illustrated in FIG. 14 are one set of nozzles 291, 292, 293, and 294 extending from one set of discharge conduits 101104 respectively. The direction of rotation of the separator is indicated by arrow 295. As illustrated in these figures, the nozzles are directed to discharge fluid into annular chambers 221-224 in a direction tangent or generally tangent to the circle of rotation and in a direction opposite to the direction of rotation to produce torque to aid in turning the separator thereby minimizing the power required for rotating the separator.

Referring now to FIGS. 3 and 17-21, there will be described a vibratory cylindrical screen employed in the annular passage D which acts to convey material up the annular passage D by vibration and in addition acts to settle the high density particles and to float the lighter particles radially inward within the annular passage D. It also acts to reduce the viscosity of a thixatropic fluid thereby promoting settling. Centrifuging causes the predominant settling of the particles dependent upon the density and particle size while the vibrating screen causes classification of material by density alone since the higher density particles will float the lower density particles. In FIGS. 3, 17, and 21, the screen is identified by reference numeral 301 and is a cylindrical member having apertures or perforations 303. The screen is located within the annular passage D near the wall of cylinder 23 and extends from near the top of the separator downward to near the end of chamber D. The apertures or perforations enhance movement of the material and prevent the weight of the settled material from producing hoop tension stresses. Instead of a screen, the member 30] may be a solid cylinder having a knurled or rough surface on its inside. Connected to the top end of the screen 301 are four spaced slider blocks 305 which vibrate the screen 301 in chamber D. In FIG. 3, only one slider block and control mechanism is illustrated on the left although three other slider blocks are provided spaced apart. Each slider block 305 is vibrated by a connecting rod 306 which is connected to an eccentric radially extending shaft which is rotated back and forth by an actuator block similar to those described above. In FIG. 17, the actuator block is illustrated as 321 and has coupled thereto by way of torque arms 323 and bolts 325, four radial shafts 327 which rotate back and forth within sleeves 329 as the actuator block 321 is axially moved back and forth by a thrust tube 249. See FIG. 3. As illustrated in FIGS. 18 20, each radial rod 327 has an eccentric end 327A which fits into a sleeve 335. Sleeve 335 is connected to eccentric end 327A by bolt 333. Sleeve 335 also extends through an aperture 306A formed through the top of rod 306, for movement therein, while end portion 335A of sleeve 335 extends into an aperture 337 formed into plate member 339 in alignment with the axis of rod 327. Plate member 339 is connected to annular ring 204 by way of frame 341 and bolts 343. In FIG. 19, plate member 339 is removed for purpose of clarity. As shaft 327 rotates back and forth within sleeve 329. eccentric end 327A will oscillate the end of connecting rod 306 within the space 341A formed in frame 341 to cause the screen 301 to oscillate back and forth within the chamber D. As indicated above, as the screen 301 oscillates, it will act to convey the material up the annular passage D and to promote settling or classification of the material in the passage D.

As is illustrated in FIG. 22, a collar 351 is attached to the top end of the thrust tube 249 which forms the piston of a hydraulic cylinder 353 for periodically moving the tube 249 up and down to impart vibration to the screen 301. Fluid to the cylinder 353 is controlled by a suitable control system 355.

In order to provide enhanced separation of the paraticles flowing through passages Gl-G6 an annular filter may be provided next to the inner surface of the wall of cylinder 25 in the flow path of the fluid flowing through passages Gl-G6. Such a filter is illustrated at 361 in FIG. 2 and may be of the conventional type, having filtering apertures of a size for example, ,of -10 microns. It may be constructed of woven wire or may be formed of sintered metal with the desired small passages extending therethrough The filter will have its opposite ends connect to the cylinder 25 for support purposes In order to clean the filter, in the event that particles become caked on the outside surface of the filter, the selector valve (rod 125 and cylinders 151 and 123) may be positioned to block all material flow through the bypass chamber H. When this occurs, the differential pressure across the filter will be eliminated and due to the centrifugal force imparted by the spinning action of the separator, the filter cake on the exterior of the filter will break away. Although not shown, means may be employed to automatically move control rod 125 downward to close conduits 131 and openings 121 for a desired period of time whereby the filter will be self-cleaning.

In one embodiment, the separator has a length of about feet while cylinder 23 has a diameter of about 38 inches. The annular space D between cylinders 23 and 25 is about two inches. The truncated cone 25 has a small diameter of about eleven inches. Vibrator screen 301 has a length of about l7 feet while filter 361 has a length sufficient to extend across all of the apertures Gl-G6. Each set of apertures G1-G6 include about 300 apertures whereby passages Gl-G6 cornprise a total of 1800 apertures. The distance between each set of apertures is about inches. The apertures G1 have a diameter of about Ms of an inch while the apertures G6 have a diameter of about 5/16 of an inch. The flow area of conduits 71-79 is greater than that of the lower conduits or passages extending into cylinder 27 from chambers H and S, however, the flow rate through these latter passages and conduits is greater than that through conduits 79-79. In one embodiment, the separator may be spun or rotated at a rate of 1750 rpm. In the embodiment disclosed wherein the separator is being used for separating the materials of drilling fluid, gases will be separated and discharged through port 85 while water or oil will be separated and discharaged through Archimedes sprial 87. The remaining materials will be separated and discharged through annular passages 91-94 and conduits 101-104.

Although the separator has been described as separating materials into six densities. it is understood that it may be modified to separate the materials into more or less densities. In addition, if desired, it may be modifled further to separate the materials flowing through cylinder 27 into materials of more than two densities. Moreover. the system may be modified to discharge from cylinder 27 materials of only one average density. It is to be understood that the passages (ll-G6 may include more or less than six sets. The separator also may be modified if desired, to completely block flow through main passage S when the control rod is moved to a given position. This may be done by modifying the lengths of cylinders 141A and 143A and by connecting additional sleeves to rod 125 similar to 151 whereby conduits 141, 143, and 145 are blocked to flow of fluid and conduit 113 and 121 are fully open. Passage 147 may be blocked by a suitable annular member connected to the lower end of cylinder 123. It is to be understood further that the flow turner defined by conduits 71-79 may include more than nine rows of conduits or less. In addition, more than one row of conduits may be provided for conduits 131 and 113 respectively, and the flow turner defined by radial conduits 141, 143, and 145 may have more than three rows of conduits or less.

I claim: 1. A multiple density separator comprising: wall structure forming an outer chamber, wall structure forming an inner chamber located within said outer chamber, said inner and outer chambers being fixedly connected together, means for rotating said chambers, said inner chamber having outside wall surface spaced from inside wall surface of said outer chamber forming a material separating chamber therebetween, an inlet formed through said wall structure of said outer chamber at one end of said separating chamber for allowing the flow of material from said inlet toward the other end of said separating chamber while said chambers are rotating, inward flow means formed through said wall structure of said inner chamber for flowing material next to the outside wall of said inner chamber inward into said inner chamber, discharge means for discharging out of said separator, the materials flowing inward into said inner chamber, and separate flow means including flow conduit means formed through said wall structure of said outer chamber downstream of said inward flow means for flowing material downstream of said inward flow means out of said separating chamber. 2. The separator of claim 1, comprising: means for separating the material flowing inward into said inner chamber into materials of at least two different densities, said discharge means including means for discharaging in separate flow paths said materials separated into said two different densities. 3. The separator of claim 1 wherein: said separate flow means separates material down stream of said inward flow means into materials of a plurality of densities. 4. The separator of claim 3, comprising: means for separating the material flowing inward into said inner chamber into materials of at least two different densities, said discharge means including means for discharging in separate flow paths said materials separated into said two different densities. 5. A separator comprising:

structure including a cylindrical member forming an outer chamber,

structure including a cylindrical member forming an inner chamber located within said outer chamber.

said cylindrical members of said inner and outer chambers being fixedly connected together,

means for rotating said chambers,

said inner chamber having outside wall surface spaced from inside wall surface of said outer chamber forming a material separating chamber, there between,

an inlet formed through said structure of said outer chamber at one end of said separating chamber and at a first end of said separator, for allowing the flow of material from said inlet toward the other end of said separating chamber, while said chambers are rotating,

inward flow means formed through said cylindrical member of said inner chamber to allow material next to the outside wall of said inner chamber to flow inward into said inner chamber,

separate flow means including flow conduit means formed through said cylindrical member of said outer chamber downstream of said inward flow means for flowing material downstream of said inward flow means out of said separating chamber,

a discharge chamber located in said inner chamber and having one end located near said first end of said separator and a discharge end extending through the other end of said separator,

said discharge chamber being rotatable with said inner and outer chambers,

inner passage means for allowing said material flowing inward into said inner chamber to flow into said discharge chamber,

means for adjusting the size of said inner passage means to vary the fiow rate of material flowing through said inner passage means into said discharge chamber, and

discharge means coupled to said discharage end of said discharge chamber for discharging material from said discharge chamber.

6. A separator comprising:

structure forming an outer chamber,

structure forming an inner chamber located within said outer chamber,

means for rotating said chambers,

said inner chamber having outside wall surface spaced from inside wall surface of said outer chamber forming a material separating chamber, therebetween,

an inlet in fluid communication with one end of said separating chamber at a first end of said separator for allowing the flow of material from said inlet toward the other end of said separating chamber while said chambers are rotating,

a plurality of axially spaced passages extending through the wall of said inner chamber to allow material next to the outside wall of said inner chamber to flow inward.

separate flow means located downstream of said axially spaced passages for flowing material in said separating chamber downstream of said axially spaced passages out of said separating chamber,

a discharge chamber located in said inner chamber and having one end located near said first end of said separator and a discharge end extending through the other end of said separator,

wall means located between said inner chamber and said discharge chamber for providing at least two different paths extending from said axially spaced passages toward said first end of said separator,

a first of said two different flow paths extending from a group of upstream passages,

the second of said two different flow paths extending from a group of downstream passages,

first inner passages formed in said discharge chamber at said one end thereof in communication with said first of said two different flow paths,

second inner passages formed in said discharge chamber at said one end thereof in communication with said second of said two different flow paths,

means for adjusting the size of said first and second inner passages to selectively vary the flow rate of material flowing through said two different flow paths, and

discharge means coupled to said discharge end of said discharge chamber for discharging material from said discharge chamber.

7. The separator of claim 6 wherein said adjusting means comprises:

axially movable rod means extending into said discharge chamber through said discharge end, and

valve means connected to said rod means for opening and closing said first and second inner passages when said rod means is moved to different axial positions.

8. The separator of claim 6, comprising:

flow turner means for positioning the fluid flowing through said passages at different radial positions dependent upon the density of the material 9. The separator of claim 8 wherein said flow turner means comprises:

axially spaced conduit means extending radially inward into said inner chamber from said downstream passages,

said conduit means extending inward to different radial positions,

the downstream conduit means having lengths less than the upstream conduit means.

10. The separator of claim 9, wherein:

said wall means has an end of large cross-section and an end of smaller cross-section,

said end of large cross-section being connected to the inside wall of said inner chamber at a position between said downstream and upstream passages,

said end of smaller cross-section extending around said one end of said discharge chamber,

conduit means extending from said discharge charn ber through said wall means into said first flow path, and

conduit means within said wall means and extending from said second flow path to the interior of said discharge chamber.

11. The separator of claim 10 wherein said flow turner means comprises:

axially spaced inner conduit means extending radially inward from the wall of said discharge chamber,

said axially spaced inner conduit means extending inward to different radial positions,

the downstream conduit means extending into said discharge chamber having lengths less than the upstream conduit means extending into said dis charge chamber.

[2. A separator comprising:

structure forming an outer cylindrical chamber,

structure forming an inner cylindrical chamber located within said outer cylindrical chamber, means for rotating said chambers,

said inner chamber having outside wall surface spaced from the inside wall surface of said outer chamber forming an annular material separating chamber, therebetween,

an inlet in fluid communication with one end of said annular material separating chamber at a first end of said separator for allowing the flow of material from said inlet toward the other end of said separating chamber, while said chambers are rotating, a plurality of axially spaced passages extending through the wall of said inner chamber to allow material next to the outside wall of said inner chamber to flow inward,

discharge means in communication with said passages for discharging out of said separator, material flowing through said passages,

separate flow means in fluid communication with said annular material separating chamber downstream of said axially spaced passages for flowing material in said annular material separating chamber downstream of said axially spaced passages, out of said annular material separating chamber,

said separate flow means comprising a plurality of annular passages rotatable with said inner and outer cylindrical chambers and having openings in communication with said annular material separating chamber at different radial positions,

flow conduit means extending from each annular passage out of said rotatable cylinders, said flow conduit means associated with each annular passage having discharge nozzle means located at different radial positions outside of said outer cylindrical chamber to discharge the flow from each annular passage at a different radial position. and

means for separately receiving the material discharged from each annular passage through its associated flow conduit means.

13. The separator of claim 12 wherein said nozzle means extends generally tangent to the circles formed upon rotation thereof and in directions opposite to the direction of rotation,

14. The separator of claim 12 wherein said flow conduit means comprise:

at least one flow conduit extending from each annular passage radially out of said rotatable cylinders,

each flow conduit having an aperture formed therethrough within the radius of its associated annular passage,

a rotatable sleeve surrounding each flow conduit and having an aperture formed therethrough at about the radius of the aperture of its associated flow conduit, and adapted to be aligned therewith for providing an inlet from the annular passage into the flow conduit, and

means for rotating each sleeve about its axis to vary the size of the fluid inlet into the flaw conduits.

15. A separator comprising:

structure forming an outer chamber,

structure forming an inner chamber located within said outer chamber,

means for rotating said chambers,

said inner chamber having outside wall surface spaced from inside wall surface of said outer chamber forming a material separating chamber, therebetween,

an inlet in fluid communication with one end of said separating chamber at a first end of said separator for allowing the flow of material from said inlet toward the other end of said separating chamber while said chambers are rotating,

a plurality of axially spaced passages extending through the wall of said inner chamber to allow material next to the outside wall of said inner chamber to flow inward,

discharge means in communication with said passages for discharging out of said separator, material flowing through said passages,

separate flow means located downstream of said axially spaced passages for flowing material in said separating chamber downstream of said axially spaced passages, out of said separating chamber,

vibratory means located between the outside wall surface of said inner chamber and the inside wall surface of said outer chamber, and

means for vibrating said vibratory means while said chambers are rotating.

16. The separator of claim 5, comprising:

filter means located next to the inside wall of said inner chamber behind said inward flow means. 

1. A multiple density separator comprising: wall structure forming an outer chamber, wall structure forming an inner chamber located within said outer chamber, said inner and outer chambers being fixedly connected together, means for rotating said chambers, said inner chamber having outside wall surface spaced from inside wall surface of said outer chamber forming a material separating chamber therebetween, an inlet formed through said wall structure of said outer chamber at one end of said separating chamber for allowing the flow of material from said inlet toward the other end of said separating chamber while said chambers are rotating, inward flow means formed through said wall structure of said inner chamber for flowing material next to the outside wall of said inner chamber inward into said inner chamber, discharge means for discharging out of said separator, the materials flowing inward into said inner chamber, and separate flow means including flow conduit means formed through said wall structure of said outer chamber downstream of said inward flow means for flowing material downstream of said inward flow means out of said separating chamber.
 2. The separator of claim 1, comprising: means for separating the material flowing inward into said inner chamber into materials of at least two different densities, said discharge means including means for discharaging in separate flow paths said materials separated into said two different densities.
 3. The separator of claim 1 wherein: said separate flow means separates material downstream of said inward flow means into materials of a plurality of densities.
 4. The separator of claim 3, comprising: means for separating the material flowing inward into said inner chamber into materials of at least two different densities, said discharge means including means for discharging in separate flow paths said materials separated into said two different densities.
 5. A separator comprising: structure including a cylindrical member forming an outer chamber, structure including a cylindrical mEmber forming an inner chamber located within said outer chamber, said cylindrical members of said inner and outer chambers being fixedly connected together, means for rotating said chambers, said inner chamber having outside wall surface spaced from inside wall surface of said outer chamber forming a material separating chamber, therebetween, an inlet formed through said structure of said outer chamber at one end of said separating chamber and at a first end of said separator, for allowing the flow of material from said inlet toward the other end of said separating chamber, while said chambers are rotating, inward flow means formed through said cylindrical member of said inner chamber to allow material next to the outside wall of said inner chamber to flow inward into said inner chamber, separate flow means including flow conduit means formed through said cylindrical member of said outer chamber downstream of said inward flow means for flowing material downstream of said inward flow means out of said separating chamber, a discharge chamber located in said inner chamber and having one end located near said first end of said separator and a discharge end extending through the other end of said separator, said discharge chamber being rotatable with said inner and outer chambers, inner passage means for allowing said material flowing inward into said inner chamber to flow into said discharge chamber, means for adjusting the size of said inner passage means to vary the flow rate of material flowing through said inner passage means into said discharge chamber, and discharge means coupled to said discharage end of said discharge chamber for discharging material from said discharge chamber.
 6. A separator comprising: structure forming an outer chamber, structure forming an inner chamber located within said outer chamber, means for rotating said chambers, said inner chamber having outside wall surface spaced from inside wall surface of said outer chamber forming a material separating chamber, therebetween, an inlet in fluid communication with one end of said separating chamber at a first end of said separator for allowing the flow of material from said inlet toward the other end of said separating chamber while said chambers are rotating, a plurality of axially spaced passages extending through the wall of said inner chamber to allow material next to the outside wall of said inner chamber to flow inward, separate flow means located downstream of said axially spaced passages for flowing material in said separating chamber downstream of said axially spaced passages out of said separating chamber, a discharge chamber located in said inner chamber and having one end located near said first end of said separator and a discharge end extending through the other end of said separator, wall means located between said inner chamber and said discharge chamber for providing at least two different paths extending from said axially spaced passages toward said first end of said separator, a first of said two different flow paths extending from a group of upstream passages, the second of said two different flow paths extending from a group of downstream passages, first inner passages formed in said discharge chamber at said one end thereof in communication with said first of said two different flow paths, second inner passages formed in said discharge chamber at said one end thereof in communication with said second of said two different flow paths, means for adjusting the size of said first and second inner passages to selectively vary the flow rate of material flowing through said two different flow paths, and discharge means coupled to said discharge end of said discharge chamber for discharging material from said discharge chamber.
 7. The separator of claim 6 wherein said adjusting means comprises: axially movable rod means extending into saiD discharge chamber through said discharge end, and valve means connected to said rod means for opening and closing said first and second inner passages when said rod means is moved to different axial positions.
 8. The separator of claim 6, comprising: flow turner means for positioning the fluid flowing through said passages at different radial positions dependent upon the density of the material.
 9. The separator of claim 8 wherein said flow turner means comprises: axially spaced conduit means extending radially inward into said inner chamber from said downstream passages, said conduit means extending inward to different radial positions, the downstream conduit means having lengths less than the upstream conduit means.
 10. The separator of claim 9, wherein: said wall means has an end of large cross-section and an end of smaller cross-section, said end of large cross-section being connected to the inside wall of said inner chamber at a position between said downstream and upstream passages, said end of smaller cross-section extending around said one end of said discharge chamber, conduit means extending from said discharge chamber through said wall means into said first flow path, and conduit means within said wall means and extending from said second flow path to the interior of said discharge chamber.
 11. The separator of claim 10 wherein said flow turner means comprises: axially spaced inner conduit means extending radially inward from the wall of said discharge chamber, said axially spaced inner conduit means extending inward to different radial positions, the downstream conduit means extending into said discharge chamber having lengths less than the upstream conduit means extending into said discharge chamber.
 12. A separator comprising: structure forming an outer cylindrical chamber, structure forming an inner cylindrical chamber located within said outer cylindrical chamber, means for rotating said chambers, said inner chamber having outside wall surface spaced from the inside wall surface of said outer chamber forming an annular material separating chamber, therebetween, an inlet in fluid communication with one end of said annular material separating chamber at a first end of said separator for allowing the flow of material from said inlet toward the other end of said separating chamber, while said chambers are rotating, a plurality of axially spaced passages extending through the wall of said inner chamber to allow material next to the outside wall of said inner chamber to flow inward, discharge means in communication with said passages for discharging out of said separator, material flowing through said passages, separate flow means in fluid communication with said annular material separating chamber downstream of said axially spaced passages for flowing material in said annular material separating chamber downstream of said axially spaced passages, out of said annular material separating chamber, said separate flow means comprising a plurality of annular passages rotatable with said inner and outer cylindrical chambers and having openings in communication with said annular material separating chamber at different radial positions, flow conduit means extending from each annular passage out of said rotatable cylinders, said flow conduit means associated with each annular passage having discharge nozzle means located at different radial positions outside of said outer cylindrical chamber to discharge the flow from each annular passage at a different radial position, and means for separately receiving the material discharged from each annular passage through its associated flow conduit means.
 13. The separator of claim 12 wherein said nozzle means extends generally tangent to the circles formed upon rotation thereof and in directions opposite to the direction of rotation.
 14. The separator of claim 12 whErein said flow conduit means comprise: at least one flow conduit extending from each annular passage radially out of said rotatable cylinders, each flow conduit having an aperture formed therethrough within the radius of its associated annular passage, a rotatable sleeve surrounding each flow conduit and having an aperture formed therethrough at about the radius of the aperture of its associated flow conduit, and adapted to be aligned therewith for providing an inlet from the annular passage into the flow conduit, and means for rotating each sleeve about its axis to vary the size of the fluid inlet into the flow conduits.
 15. A separator comprising: structure forming an outer chamber, structure forming an inner chamber located within said outer chamber, means for rotating said chambers, said inner chamber having outside wall surface spaced from inside wall surface of said outer chamber forming a material separating chamber, therebetween, an inlet in fluid communication with one end of said separating chamber at a first end of said separator for allowing the flow of material from said inlet toward the other end of said separating chamber while said chambers are rotating, a plurality of axially spaced passages extending through the wall of said inner chamber to allow material next to the outside wall of said inner chamber to flow inward, discharge means in communication with said passages for discharging out of said separator, material flowing through said passages, separate flow means located downstream of said axially spaced passages for flowing material in said separating chamber downstream of said axially spaced passages, out of said separating chamber, vibratory means located between the outside wall surface of said inner chamber and the inside wall surface of said outer chamber, and means for vibrating said vibratory means while said chambers are rotating.
 16. The separator of claim 5, comprising: filter means located next to the inside wall of said inner chamber behind said inward flow means. 